Open4DFlow is an open-source, vendor-agnostic 4D flow MRI framework built with PyPulseq. It provides ready-to-run pulse sequences and a full analysis pipeline, from acquisition to velocity reconstruction to displacement and strain calculation.
sequences/– Pulse sequence scripts that generate.seqfiles for direct execution.analysis/– Post-processing pipeline for reconstructing velocity,displacement ans strain fields from acquired 4D flow data.
- Compressed sensing acceleration – The undersampled sequences use poisson disc k-space undersampling, enabling significantly faster acquisitions.
- Vendor-agnostic gradient handling – A gradient probing sequence identifies the physical direction of each gradient axis at the used scanner, ensuring correct velocity direction interpretation across scanner vendors.
- Standardised file formats – The analysis pipeline outputs data in ORMIR-MIDS format (NIfTI + JSON sidecar), ensuring compatibility with other muscle and cardiovascular MRI tools.
- Open reconstruction – Image reconstruction is performed with the BART toolbox, with optional GPU acceleration.
See the README files in the corresponding subfolders for more information on how to install and run each component of the pipeline.
These sequences are intended for research and educational purposes. Parameters, timing, and gradients should be carefully verified before in vivo use and potentially adapted to you system.